This paper delves into the age-old debate over free will and determinism as raised in the work that held popular culture transfixed for the better part of a decade: the Harry Potter novels. Though the final book was published in 2007, thus revealing the outcome of the series’ cliffhanger, this paper (written in 2006) argues that the books embody a Catholic moral theology and sensibility. The central figure through which those ideas are most fully expressed is not the title character, whose moral sense remains less than completely developed throughout the first six novels, but through another major figure in the series. That character’s mysterious past is whimsically explored here and tied to author J.K. Rowling’s larger purpose: to make the book a vivid object lesson in the power of love, forgiveness, and redemption – all essential elements of the Augustinian notion of free will.